Positive pile wire motion for pile fabric textile machines

ABSTRACT

Positive means shifts selected pile wires forwardly and rearwardly to present loop forming stages of different heights thereon to means for looping pile yarns over the pile wires on a machine for forming pile fabrics.

D United States Patent 1191 1111 3,741,255 Ostler June 26, 1973 [54] POSITIVE PILE WIRE MOTION FOR PILE 2,318,080 5/1943 Keen 139/37 X FABRIC TEXTILE MACHINES 18681231 "1959 2,808,072 10/1957 [75] Inventor: Carl Edward Ostler, Eden, NC. 2,3 0, 4 11 195s 3,140,592 7/l964 [73] Assgnee' mums Mills Eden 3,677,206 7/1972 Maclsaac, Jr. et a1 112/79 R [22] Filed: Feb. 9, 1972 [21] APPL 224 23 Primary Examiner-James Kee Chi Attorney-Donald M. Seltzer [52] [1.8. CI. 139/46, 66/85 R, 112/79 R [51] Int. Cl D03d 39/20 [57] ABSTRACT [58] Field of Search l39/46, 47, 37, 38,

139/39 1 166; 66/85 R; 1 12/79 R Positive means shifts selected pile wires forwardly and rearwardly to present loop forming stages of different [56] References cued heights thereon to means for looping pile yarns over the UNITED STATES PATENTS pile wires on a machine for forming pile fabrics.

2,973,785 3/1961 Park et a1. 139/46 .14 Claims, 3 Drawing Figures POSITIVE PILE WIRE MOTION FOR PILE FABRIC TEXTILE MACHINES This invention relates to machines for forming pile fabrics, such as looms, knitting machines and tufting machines, of the type having a plurality of elongate pile wires extending in the longitudinal direction of the fabric and which are selectively shifted longitudinally to present respective loop forming stages thereon of different heights to the loop forming zone where pile yarns are looped over the pile wires in the production of variant-height pile fabrics.

Generally, in machines of this type, each pile wire has a free front end portion forming a low pile forming surface or stage thereon, and a relatively high pile forming surface or stage is spaced rearwardly from the free end of each pile wire. As far as is known, such pile wires have been shifted back and forth heretofore under control of a pattern device with some form of mechanism for positively moving selected pile wires in one direction only longitudinally of the fabric, but wherein spring means were utilized to return the pile wires in the opposite direction. It is well known that springs are subject to fatigue and thus require replacement from time to time. Also, the springs should be relatively strong to ensure that the selected pile wires are returned to the desired position with the desired stages thereof properly positioned relative to the pile yarn looping means.

Consequently, the mechanism for positively moving the pile wires in one direction is not only subjected to the inertial forces of the pile wires, but such mechanism also must overcome the opposing forces of the springs in order to move the selected pile wires. This places the control mechanism under undue strain, and causes undue wear and even rupture of parts of the mechanism.

In a well-known loom, for example, pile wires having pile forming stages of different heights are employed which are shifted forwardly by individual springs, and they are pulled and shifted rearwardly by means of the cords of a Jacguard pattern device. Such cords extend rearwardly from the rear portions of the respective pile wires, pass under a guide bar, and then pass upwardly to the Jacguard pattern device. The stresses and strains to which the cords are subjected, and the rubbing of the cords against the guide bar, cause the cords to become worn to such extent that they have to be replaced periodically.

It is an object of this invention to provide an improved control mechanism for pile wires of the type described, which obviates the problems attendant to the use of springs mentioned above by positively shifting the pile wires both forwardly and rearwardly longitudinally of the pile fabric being formed.

It is a more specific object of this invention to provide an improved control mechanism comprising a positively driven reciprocating member movable in the longitudinal direction in timed relation to means for looping pile yarns over the pile wires, with pattern controlled means for selectively transmitting motion from the reciprocating member to selected pile wires to present different heights of loop forming stages of the selected pile wires to the pile yarn looping means.

According to a preferred embodiment of the invention, each of the pile wires is provided with a substantially vertically movable element positioned rearwardly of the loop forming stages thereof and normally occupying inoperative position with respect to the aforementioned reciprocating member. A pattern device is operatively connected to the vertically movable elements for selectively displacing the same to operative positions in timed relation to the movement of the reciprocating member, and the reciprocating member is provided with means for receiving each such element displaced to the operative position for transmitting reciprocation thereto to shift the respective pile wires and present different heights of stages thereon to the pile yarn looping means.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which FIG. 1 is a schematic longitudinal sectional view through a pile fabric forming machine embodied in a loom equipped with a preferred embodiment of my improved pile wire control mechanism;

FIG. 2 is an enlarged fragmentary view of the pile wire control mechanism of FIG. 1, with parts broken away, showing the pile wires in a forward operative position; and

FIG. 3 is a view similar to FIG. 2 showing one of the pile wires occupying the forward operative position and showing another of the pile wires occupying a rearward operative position.

Referring more specifically to the drawings, the pile fabric forming machine there shown is in the form of a loom of the type having means for weaving a base fabric 10 from warp yarns 11 and weft yarns 12, wherein the weft shots or weft yarns 12 are beat up against the fell of the fabric 10 by a reed 13 following insertion thereof into a shed formed of the warp yarns 11 by a suitable shed forming means or heddles 14, as is usual. The loom is provided with a weftwise or transverse row of closely spaced elongate pile wires 15 whose forward portions overlie the fabric adjacent the fell thereof, and suitable means are provided, in the form of pile yarn guides 16, for looping continuous pile yarns 17 over and across the respective pile wires 15.

Pile wires 15 are of the general type disclosed in Stovalls U. S. Pat. No. 2,808,072, dated Oct. 1, 1957, in that they extend in the warpwise or longitudinal direction of fabric 10 and are provided with respective longitudinally arranged variant-height loop forming surfaces or stages on their forward portions. As shown, the free front end of each pile wire 15 is provided with a relatively low stage 15a, with a relatively high stage 15b spaced rearwardly of the free front end of the low stage 15a. As preferred, the forward portion of each high stage 15b overlies and is spaced above the rear portion of the respective low stage 15a to accommodate the upper bights of a few of the previously formed relatively low pile loops L-l extending over the low stage when the corresponding pile wire 15 occupies the forward operative position. The high stage 15b of the respective pile wire 15 then is positioned in the loop forming zone so that a corresponding pile yarn 17 is looped thereover by a respective pile yarn guide 16 as in forming high loops L-2 thereover (FIG. I). A suitable pattern device 20, preferably a Jacguard, also is provided for effecting selection of pile wires 15 in a novel manner according to the present invention, as will be later described.

The means for inserting weft yarns 12 in the warp shed and the means for supporting and operating such weft inserting means, the reed 13, heddles l4, pile yarn guides 16 and pattern device 20 in proper timed relationship may be substantially as disclosed in Mobergs U. S. Pat. No. 2,860,664, dated Nov. l8, 1958, the disclosure of which is incorporated herein by way of reference. Accordingly, a more detailed description of the loom is deemed unnecessary. It should be noted, however, that pile yarn guides 16 move downwardly between pile wires 15 from a position spaced above the fabric and the pile wires to move the respective pile yarns 17 through the warp shed and in front of reed I3, whereupon a weft shot is inserted through the open warp shed and over the pile yarns 17, as shown in FIG. 1.

Following the insertion of the weft shot, pile yarn guides 16 move upwardly and are shifted laterally over and across respective pile wires 15 as reed 13 heats up the weft shot, along with the portions of pile yarns 17 then extending downwardly from pile wires 15, against the fell of base fabric to form a corresponding weftwise row of pile loops over pile wires 15. Thereafter, a cycle in the operation of the loom is repeated, in the course of which pile yarns 17 are looped over respective pile wires 15 incident to the downward movement of pile yarn guides 16 so that the pile loops are formed over pile wires 15 in the opposite direction from that in which they were formed in the previous weftwise row of such loops. Since pile yarns 17 are suitably tensioned, as each successive weftwise row of pile loops is formed over the pile wires, the last previously formed row of pile loops is tightened against the corresponding stages of the respective pile wires 15.

According to the invention, an improved control mechanism is provided for positively and selectively shifting pile wires 15 both forwardly and rearwardly longitudinally of base fabric 10 to present the different heights of loop forming stages 15a, 15b thereof to the pile yarn looping means or guides 16 in timed relation to the vertical movement of pile yarn guides 15. The control mechanism includes a positively driven reciprocating means with patterned controlled means for se-- lectively transmitting motion from the reciprocating means to selected pile wires.

In its preferred embodiment, the positively driven reciprocating means may take the form of an elongate transverse reciprocating member or bar 25 movable in the longitudinal direction of base fabric 10 and including front and rear spaced apart walls 25a, 25b defining an elongate open-bottomed groove or recess 25c therebetween adapted to be engaged by selected substantially vertically movable elements or abutments 26 carried by the respective pile wires 15 and arranged in a row extending transversely of the longitudinal direction of base fabric 10 and rearwardly of loop forming stages 15a, 151;. As shown, pile wires 15 normally occupy forward operative position with the vertically movable abutments 26 thereof underlying the path of reciprocation of at least the front wall 25a of reciprocating bar 25, and with the high stages 15b of the respective pile wires 15 positioned in the loop forming zone. In this regard, it is to be noted that rear wall 25b of reciprocating bar 25 projects downwardly below the plane of front wall 25a for a purpose to be later described.

As shown, each abutment 26 projects upwardly from and may be formed integral with the rear portion of a pivoted selector arm or lever 26a whose front portion is pivotally connected to an elongate pile wire extension or guide bar 150. Each guide bar 150 may be formed integral with the stem of the respective pile wire 15 or it may be suitably connected to such stem by an interlocking connection 15d, as shown, so that pile wires 15 may be readily detached from the respective guide bars 15c. Suitable elongate and serrated or grooved guide members or combs 30 are stationarily mounted on the loom frame and extend transversely thereof for guiding and maintaining adjacent pile wire extensions 15c and adjacent levers 26a in the desired closely spaced relationship across the width of base fabric 10.

The usual cords 20a of pattern device 20 are attached to respective levers 26a and extend upwardly therefrom to pattern device 20. When any cords 20a are relaxed and occupy lowered positions, and respective pile wires 15 occupy forward positions, the rear ends of the respective levers 26a occupy lowered or inoperative position resting upon a stationary transverse support means 31 carried by the loom frame. The upper ends of the respective abutments 26 then are spaced below the level of front wall 25a of reciprocating bar 25 and also are preferably positioned below the level of the lower edge of rear wall 25b.

Whenever pattern device 20 calls for selection of any pile wires 15 to present relatively low stages 15a thereof to pile yarn looping means or guides 16, pattern device 20 operates in a known manner to lift corresponding cords 20a and raise respective levers 26a. At

- the time that any levers 26a are raised, reciprocating bar 25 occupies and dwells in its forwardmost position (FIG. 2) with its recess 250 so positioned that selected abutments 26 are received in recess 25c while those levers 260 not selected remain resting upon support means 31. It follows that, upon subsequent rearward movement of bar 25, selected pile wires 15 are pulled rearwardly a predetermined distance to move high stages 15b thereof rearwardly to inoperative position with respect to pile yarn guides 16 and thereby to present respective low stages 15a to the pile yarn looping means, which then forms relatively low pile loops L-l over the thus presented low stages 15a.

Of course, relatively high pile loops L-2 are then being formed over the high stages 15b of any pile wires 15 whose abutments 26 have not been lifted into recess 25c of bar 25. To insure that high stages 15b of those pile wires whose levers 26:: have not been selected will remain in forward operative position during operation of the loom, a transverse restraining or limiting member 32 is provided and projects upwardly from the rear portion of support means 31 immediately rearwardly of any lever 26a resting on support means 31. Thus, restraining member 32 prevents any pile wires 15 whose levers 26a occupy lowered position from being moved rearwardly as a result of vibration of the loom and/or the relative rearward movement of adjacent selected pile wires 15. The upper edge of restraining member 32 is spaced below the path of movement of rear wall 25b of bar 25 so that restraining member 32 will not obstruct forward movement of reciprocating bar 25 and so that restraining member 32 also serves as a guide means for levers 26a, as will be presently described.

During each loop forming cycle of the loom, a complete reciprocation is imparted to reciprocating bar 25 by means to be later described, during which reciprocating bar 25 dwells in its rearmost position for a sufficient period of time to insure that pile yarns 17 are properly formed into loops over the low stages a of selected pile wires 15. Thus, as preferred, pattern device 20 releases all of any selected levers 26a while reciprocating member dwells in rearmost position. In so doing, pattern cords 20a are relaxed and previously selected levers 26a drop upon restraining means 32 with corresponding abutments 26 then positioned below the level of front wall 25a and in front of the lower portion of rear wall 25b of reciprocating bar 25.

Generally, although levers 26a are of light weight, the weight thereof is such that any previously selected lever 26a will gravitate and come to rest against restraining means 32 and thereby withdraw the corresponding abutment 26 from recess 250. However, suitable means may be provided to insure that frictional forces between reciprocating bar 25 and abutments 26 will not cause any selected abutments 26 and levers 26a to remain in raised position when released by cords 20a. To this end, a lightweight transverse weighting bar 33 rests upon the rear portions of all the levers 26a, between abutments 26 and cords 20a, when all the levers 26a occupy lowered position resting upon supporting means 31. Of course, bar 33 rests upon only those levers 26a which have been selected as any of the levers 26a are raised to the operative position with respect to reciprocating bar 25. Any suitable means may be provided for guiding weighting bar 33 in the course of vertical movement thereof.

After the levers 26a of previously selected and rearwardly moved pile wires 15 have been released by pattern device 20, a forward stroke is imparted to reciprocating bar 25, during which rear wall 25b moves in engagement with the rear edges of corresponding levers 260 as they ride upon restraining member 32, thereby pushing the respective pile wires 15 forwardly to present high stages 15b thereof to pile yarn looping means 16. As reciprocating bar 25 reaches forwardmost position, it is apparent that all of the previously selected levers 26a drop onto supporting means 31, forwardly of restraining means 32, to complete a cycle in the operation of the pile wire control mechanism.

As heretofore indicated, reciprocating bar 25 is positively driven in both the forward and rearward directions during each reciprocation thereof. To this end, each end portion of reciprocating member 25 has the front end of an extensibly adjustable guide rod 35 suitably attached thereto, only one of which is shown in the drawings. Each guide rod 35 is guided for longitudinal, forward and rearward, movement in a suitably bearing means 36 carried by a fixed part of the loom frame. The rear end of each guide rod 35 is connected, as by a link 37, to a crank 40 mounted on and extending outwardly from a rocker shaft 41 extending transversely of the loom and suitably journaled on the loom frame. A follower arm 42 is fixed on rocker shaft 41 and follower 43 thereon is positioned in an irregular cam groove in one side of a rotary face cam 45.The walls of groove 44 are spaced apart sufficiently only to insure that follower 43 follows the configuration of groove 44 during rotation of cam 45, thereby insuring that bar 25 and pile wires whose abutments 26 engage the same are moved positively in both forward and rearward directions longitudinally of base fabric 10.

In the particular illustrated embodiment, cam 45 is fixed on a shaft 46 suitably driven in timed relation to the operation of the weft inserting means, reed l3, heddies 14, pile yarn guides 16 and pattern device 20 so as to rotate one-half revolution for each loop forming cycle of the loom. Accordingly, cam groove 44 has two diametrically opposed high portions a, a, and two diametrically opposed relatively low portions b, b out of phase with respect to high portions a, a. In practice, it has been found desirable to provide a dwell of about 70 of each loop forming cycle) for each low portion b, b which engages follower 43 while reciprocating bar 25 occupies its rearmost position. The dwell of bar 25 may be about 60 when it occupies its forwardmost position.

It is thus seen that I have provided an improved control mechanism which positively imparts both forward and rearward movement to selected pile wires 15 in the longitudinal direction of the fabric 10 without placing any substantial load on the pattern device 20 and especially on its cords 20a. For example, in a known loom having pile wires which were shifted forwardly by individual springs and pulled rearwardly by the cords of a Jacguard pattern device, it was found that each cord was subjected to a load or tensile force of about 2 to 2.5 pounds in order to select and pull back a respective pile wire. In a typical installation of the control mechanism of this invention, however, it was found that the cords 20a of the pattern device 20 were only subjected to a load or tensile force of about 1.5 ounces, thus greatly increasing the useful life of cords 20a. The control mechanism of this invention also insures that the motion of pile wires 15 may be accurately timed with respect to the operation of reed 13, heddles l4, pile yarn guides 16 and pattern device 20, and insures that pile wires 15 are always properly positioned with respect to each other and to the pile yarn looping means during operation of the machine. The improved control mechanism also eliminates the possibility of relatively low pile loops being formed on any pile wires when it is desired that high loops be formed, as a result of any of the previously selective pile wires failing to move forward at the proper time under influence of the springs used heretofore, since reciprocating bar 25 pushes all of the previously selected pile wires 15 to the forwardmost position during each loop forming cycle of the machine.

In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only.

That which is claimed is:

1. In a machine for forming pile fabric including pile wires having loop forming stages of different heights thereon arranged longitudinally with respect to the longitudinal direction of the fabric, and means for looping pile yarns over said pile wires; the combination therewith of control mechanism operatively associated with said pile wires for selectively engaging said pile wires and for positively driving the selected pile wires both forwardly and rearwardly longitudinally of the fabric to present different heights of loop forming stages of selected pile wires to the pile yarn looping means.

2. A machine according to claim 1, wherein said eon-. trol mechanism includes reciprocating means positively driven both forwardly and rearwardly in said longitudinal direction in timed relation to said pile yarn looping means, and pattern controlled means for selectively transmitting motion from said reciprocating means to selected pile wires.

3. A machine according to claim 1, wherein said control mechanism includes a positively driven elongate reciprocating member extending transversely of said pile wires and movable in said longitudinal direction in timed relation to said pile yarn looping means, and pattern controlled means for selectively connecting said pile wires to said reciprocating member.

4. A machine according to claim 3, wherein said control mechanism further comprises a driven rotary cam having an irregular groove of substantially uniform width in one face thereof, linkage connected to said reciprocating member and having a follower fitting in said groove for transmitting positive reciprocation to .said reciprocating member.

5. A machine according to claim 3, wherein said reciprocating member comprises front and rear spaced apart walls defining an elongate open-bottomed recess therebetween, each of said pile wires normally occupying a forward position with one stage thereof occupying an operative position with respect to said pile yarn looping means, said pattern controlled means comprising a substantially vertically movable element carried by each pile wire and having a portion normally underlying said reciprocating member when it occupies a forward position in reciprocation thereof, and a pattern device operatively connected to said vertically movable elements for selectively moving the same into said recess when said reciprocating member occupies said forward position whereby said reciprocating member will impart motion to those pile wires whose vertically movable elements have been selected.

6. A machine according to claim 5, wherein said vertically movable elements are each in the form of a lever pivotally connected to and extending rearwardly from each pile wire, and an upwardly projecting abutment on each lever and normally occupying a lower inoperative position, wherein said pattern device is operable for selectively lifting said levers to move the respective abutments into an operative position in said recess in said reciprocating member. 4

7. A machine according to claim 6, including restraining means engaging and restraining any of said levers occupying said inoperative position against rearward movement and thereby restraining the respective pile wires against rearward movement during rearward movement of any pile wires whose levers have been lifted to move the respective abutments thereof into said recess.

8. A machine according to claim 7, wherein said rear wall of said reciprocating member extends downwardly below the level of the lower edge of said front wall with said selected levers being released by the pattern device when said reciprocating member occupies its rearmost position so that the levers will drop upon said restraining means, and the relationship of said rear wall to said restraining means being such that said rear wall will engage the rear edges of said levers and push the same forwardly as they slide upon the restraining means as the respective pile wires are moved to their forwardmost position.

9. A machine according to claim 8, including a weighting bar resting upon said levers to aid in causing the same to move downwardly when released by said pattern device.

10. In a machine for forming pile fabric including elongate pile wires extending longitudinally with respect to the longitudinal direction of the fabric and having respective longitudinally arranged loop forming stages of different heights thereon, and means for looping pile yarns over corresponding pile wire stages presented thereto; the combination therewith of mechanism for shifting said pile wires forwardly and rearwardly to present different heights of loop forming stages thereon to said pile yarn looping means and comprising a reciprocating member movable longitudinally of said pile wires, substantially vertically movable elements carried by the respective pile wires and arranged in a row extending transversely of the longitudinal direction of the fabric and rearwardly of said loop forming stages, said vertically movable elements normally occupying inoperative positions with respect to said reciprocating member, a pattern device operatively connected to said elements for selectively displacing the same to operative position in timed relation to movement of said reciprocating member, and said reciprocating member having means for receiving each element displaced to said operative position for transmitting reciprocation thereto to shift the respective pile wires and present different heights of stages thereon to said pile yarn looping means.

11. A machine according to claim 10, wherein said vertically movable elements are each in the form of a lever pivotally connected to and extending rearwardly from each pile wire, and an upwardly projecting abutment on each lever, and wherein said reciprocating member includes spaced apart front and rear walls defining an open-bottomed groove therebetween serving as said means for receiving said elements and occupies a position overlying said abutments of any of said levers occupying inoperative position when said reciprocating member is in its forwardmost position, and said pattern device including means for selectively lifting said levers to move the respective abutments into said groove in said reciprocating member.

12. A machine according to claim 11, including restraining means engaging and restraining any of said levers occupying said inoperative position against rearward movement and thereby restraining the respective pile wires against rearward movement during rearward movement of any pile wires whose levers have been lifted to move the respective abutments thereof into said groove.

13. A machine according to claim 12, wherein said rear wall of said reciprocating member extends downwardly below the level of the lower edge of said front wall with said selected levers being released by the pattern device when said reciprocating member occupies its rearmost position so that the levers will drop upon said restraining means, and the relationship of said rear wall to said restraining means being such that said rear wall will engage the rear edges of said levers and push the same forwardly as they slide upon the restraining means as the respective pile wires are moved to their forwardmost position.

14. A machine according to claim 13, including a weighting bar resting upon said levers to aid in causing the same to move downwardly when released by said pattern device.

t 1 i 0' I 

1. In a machine for forming pile fabric including pile wires having loop forming stages of different heights thereon arranged longitudinally with respect to the longitudinal direction of the fabric, and means for looping pile yarns over said pile wires; the combination therewith of control mechanism operatively associated with said pile wires for selectively engaging said pile wires and for positively driving the selected pile wires both forwardly and rearwardly longitudinally of the fabric to present different heights of loop forming stages of selected pile wires to the pile yarn looping means.
 2. A machine according to claim 1, wherein said control mechanism includes reciprocating means positively driven both forwardly and rearwardly in said longitudinal direction in timed relation to said pile yarn looping means, and pattern controlled means for selectively transmitting motion from said reciprocating means to selected pile wires.
 3. A machine according to claim 1, wherein said control mechanism includes a positively driven elongate reciprocating member extending transversely of said pile wires and movable in said longitudinal direction in timed relation to said pile yarn looping means, and pattern controlled means for selectively connecting said pile wires to said reciprocating member.
 4. A machine according to claim 3, wherein said control mechanism further comprises a driven rotary cam having an irregular groove of substantially uniform width in one face thereof, linkage connected to said reciprocating member and having a follower fitting in said groove for transmitting positive reciprocation to said reciprocating member.
 5. A machine according to claim 3, wherein said reciprocating member comprises front and rear spaced apart walls defining an elongate open-bottomed recess therebetween, each of said pile wires normally occupying a forward position with one stage thereof occupying an operative position with respect to said pile yarn looping means, said pattern controlled means comprising a substantially vertically movable element carried by each pile wire and having a portion normally underlying said reciprocating member when it occupies a forward position in reciprocation thereof, and a pattern device operatively connected to said vertically movable elements for selectively moving the same into said recess when said reciprocating member occupies said forward position whereby said reciprocating member will impart motion to those pile wires whose vertically movable elements have been selected.
 6. A machine according to claim 5, wherein said vertically movable elements are each in the form of a lever pivotally connected to and extending rearwardly from each pile wire, and an upwardly projecting abutment on each lever and normally occupying a lower inoperative position, wherein said pattern device is operable for selectively lifting said levers to move the respective abutments into an operative position in said recess in said reciprocating member.
 7. A machine according to claim 6, including restraining means engaging and restraining any of said levers occupying said inoperative position against rearward movement and thereby restraining the respective pile wires against rearward movement during rearward movement of any pile wires whose levers have been lifted to move the respective abutments thereof into said recess.
 8. A machine according to claim 7, wherein said rear wall of said reciprocating member extends downwardly below the level of the lower edge of said front wall with said selected levers being released by the pattern device when said reciprocating member occupies its rearmost position so that the levers will drop upon said restraining means, and the relationship of said rear wall to said restraining means being such that said rear wall will engage the rear edges of said levers and push the same forwardly as they slide upon the restraining means as the respective pile wires are moved to their forwardmost position.
 9. A machine according to claim 8, including a weighting bar resting upon said levers to aid in causing the same to move downwardly when released by said pattern device.
 10. In a machine for forming pile fabric including elongate pile wires extending longitudinally with respect to the longitudinal direction of the fabric and having respective longitudinally arranged loop forming stages of different heights thereon, and means for looping pile yarns over corresponding pile wire stages presented thereto; the combination therewith of mechanism for shifting said pile wires forwardly and rearwardly to present different heights of loop forming stages thereon to said pile yarn looping means and comprising a reciprocating member movable longitudinally of said pile wires, substantially vertically movable elements carried by the respective pile wires and arranged in a row extending transversely of the longitudinal direction of the fabric and rearwardly of said loop forming stages, said vertically movable elements normally occupying inoperative positions with respect to said reciprocating member, a pattern device operatively connected to said elements for selectively displacing the same to operative position in timed relation to movement of said reciprocating member, and said reciprocating member having means for receiving each element displaced to said operative position for transmitting reciprocation thereto to shift the respective pile wires and present different heights of stages thereon to said pile yarn looping means.
 11. A machine according to claim 10, wherein said vertically movable elements are each in the form of a lever pivotally connected to and extending rearwardly from each pile wire, and an upwardly projecting abutment on each lever, and wherein said reciprocating member includes spaced apart front and rear walls defining an open-bottomed groove therebetween serving as said means for receiving said elements and occupies a position overlying said abutments of any of said levers occupying inoperative position when said reciprocating member is in its forwardmost position, and said pattern device including means for selectively lifting said levers to move the respective abutments into said groove in said reciprocating member.
 12. A machine according to claim 11, including restraining means engaging and restraining any of said levers occupying said inoperative position against rearward movement and thereby restraining the respective pile wires against rearward movement during rearward movement of any pile wires whose levers have been lifted to move the respective abutments thereof into said groove.
 13. A machine according to claim 12, wherein said rear wall of said reciprOcating member extends downwardly below the level of the lower edge of said front wall with said selected levers being released by the pattern device when said reciprocating member occupies its rearmost position so that the levers will drop upon said restraining means, and the relationship of said rear wall to said restraining means being such that said rear wall will engage the rear edges of said levers and push the same forwardly as they slide upon the restraining means as the respective pile wires are moved to their forwardmost position.
 14. A machine according to claim 13, including a weighting bar resting upon said levers to aid in causing the same to move downwardly when released by said pattern device. 